<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>布局及样式</title>
<style type="text/css">
h1{color:red;}
.kuang,.kuang2{
border: 3px solid red;
margin-bottom: 10px;
}
.kuang2{
display: flex;
flex-direction: row;
align-items: center;
}
.item{
border: 1px solid blue;
margin: 10px;
}
span{color:blue;}
</style>
</head>
<body>
<h1>布局及样式</h1>
<div class='kuang'>
    <div class='item'>div1-块元素</div>
    <div class='item'>div2-块元素</div>
    <div class='item'>div3-块元素</div>
</div>
<div class='kuang2'>
    <div class='item'>
    <div>div1-块元素</div>
    <div>div1-块元素</div>
    <div>div1-块元素</div>
    </div>
<div class='item'>
    <div>div2-块元素</div>
    </div>
<div class='item'>
    <div>div3-块元素</div>
    <div>div3-块元素</div>
    </div>
</div>
</body>
</html>